Electropneumatic braking device for railway-cars.



No. 856,010. PATENTED JUNE 4, 1907.

' R. WIKANDER.

ELBGTROPNEUMATIG BRAKING DEVICE FOR RAILWAY CARS.

APPLIGATION FILED 1330.26, 1906.

3 SHEETS-SHEET 1.

No. 856,010. 7 I PATENTED JUNE 4, 1907.

R. WIKANDER. v ELEGTROPNEUMATIG BRAKING DEVICE FOR RAILWAY CARS.

APPLICATION FILED DBO. 26, 1906.

3 SHEETS-SHEET 2.

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PATENTED JUNE 4, 1907.

APPLICATION FILED DBO. 26, 1906.

3 SHEETS-SHEET 3.

01/ Jim? UNITE s'rrns RAGNAR WIKANDER, OF WESTERAS, SWEDEN.

ELECTROPNEUEWATEC BRAKING DEVICE FOR RAILWAY-"CARS.

Specification of Letters Patent.

Patented June 4, 1907.

Application filed December 26, 1906. Serial No. 349,409.

To all whom it may concern:

Be it known that I, RAGNAR WIKANpnR, a citizen of the Kingdom of Sweden,residing at Westeras, Sweden, have invented new an of all the brakes ofa railway-train a number of brake-systems have been proposed in which inaddition to the pneumatic valves have been used electrically eratedvalves.

In the most cases such bra e-systems are more complicated than thepneumatic. systems on account of the increased number of valves, andnotwithstanding the said electropneumatic systems do not ofier anyincreased safety as to their function.

The object of the present invention is to provide an electro-pneumaticbrakin -device in which only one valve-body wil be required, and inwhich an automatic adjustment of the braking-pressure can be efiected bymeans of each of the two controllingsystems.

The invention consists, chiefly, in that the valve-body controlling thecommunication between an auxiliary reservoir and the braking-cylinderand between the latter and the atmosphere is controlled by a train-pipeas well as by an electric controlling circuit in such a manner that theoperation of the said valve-body may be effected either by changmg thepressure in the train-pipe or by changing the strength of current in thesaid circuit or both simultaneously. Hereby the constructional arranement of the brake-valve will be simplifiecf and further the function ofthe electric control will be substantially similar to that of thepneumatic device. By the possibility of using the two controllingsystemssimultaneously the function will be more reliable than heretofore sothat. the brakes practically will never fail to work.

In the accompanying drawings I have illustrated substantiallydiagrammatically some embodiments of my invention.

} Figure 1 shows a longitudinal section of an 1 electro pnenmaticallyoperated valve constructed in accordance with my present in- F 1g. 2shows a diagram of the railway-car provided with air-brakes. Fig. 3shows a similar diagram with a modified form of theelectro-pneumatically operated valve in lon itudinal section. Fi 4 showsa usual trip e-valve provided witi an electric controllin device.

The valveevice' shown inFi s. 1 and 2 comprises a valve-stem 1 to whichis secured a small metal-disk 2. Two valvebodies 3 and 4 are by springs5 and 6 pressed against the said disk 2 by means of elastic rings 7 and8. Normally the said valve-bodies close bothends of the cylindricalvalve-seat v9 in the center of which ends a pipe 10 connected to thebraking-cylinder 11. Tothe stem 1 are secured two diaphragms 12 and 13and an armature 14. As is shown in the drawing the stem 1 is operatedboth by the armature 14 which is magnetized by the current in the coil15 and by the air-pressure in the chambers 16, 17, 18 and 19 on eachside of the two diaphragms 12 and 13. If the powers actuating the stem 1effect the raising of the latter, the braking-cylinder 11 will be put incommunication with the atmosphere by means of the valve 3 and thechamber 20. If the said powers lower the stem 1 the valve 4 will beopened and the air contained in the auxiliary reservoir 21 of the carwill be admitted to the braking-cylinder 11.

Referring to Fig. 2, 22 represents the airpressure-pi 0 extendingthrough the whole train and eing supplied with air from themain-reservoirs connected to the air-pumps, as is usual.

, Through the valve 23 compressed air flows into the auxiliary reservoir21 of the car, untilthe pressure in the latter is the same as in the ipe22. The braking-cylinder 11, the auxi iary reservoir 21 and the pipe 2are connected with the electro-pneumatic brakevalve, as is shown in Fig.2.

Itwill now be explained how the'apparatus works when electric current isused for braking, it being supposed that-the magnet coil 15 is firstdenergized. In as much as the air pressure in the auxiliary reservoir 21is the same as that in the air-pipe 22, the pressure in the chamber 18willbe the same as in the chamber 19 and the diaphragm 13 thus will notactuate the stem 1. If the brake in such case is applied there is anoverpressure in the braking-cylinder over the atmospheric pressure andthe said overpressure then acts 1n the chamber 17 and raises thediaphragm 12 and thus also the stem 1 which is not actuated by any otherpower. The result will be that the valye 3 is. raised and thebrakingcylinder is put in communication with the atmosphere until the,pressure in the braking- },cylinder has been reduced and cannot keep thestem 1 raised, whereupon the latter by the spring 6 will be brought backinto its nor- 'mal position. The air-pressure at which this occurs is sochosen that the brake then is released by the spring in the brakingcylinder; It will thus be understood that. if no current flows throughthe magnet, the brake will be released and remain released. It. may

now besupposed that an electric current of a certain strength be sentthrough the coil 15. The armature 14 now will be attracted, the stem 1lowered, the auxiliary reservoir 21 put in communication withthebraking-cylinder through the chamber 18 and the brake a plied untilthe increasing pressure in the braking-cylinder through the chamber 17has acted upon the diaphragm 12 and together with the pressure in thechamber 19 (which pressure now, is greater than the pressure in thechamber 18) overcomes the action of the magnet and brings the stem backinto normal position shown in Fig. 1. The brake will thereupon be keptin the said position as long as the strength of current inthe magnet isunchanged. If the pressure in-the brakincylinder is diminished, forinstance by leakage, the valve 41 will again be opened and freshcompressed air flows into the brakingcylinder, so that the determinedpressure will be maintained. If'the current in the magnet-coil 15 beincreased, the stem will again be lowered and compressed air flows intothe braking-cylinders until equilibrium has been reestablished,whereupon thester'n 1 returns into its normal position. If the strengthof current be diminished, the pressure in. the

chamber 17 will cause the valve 3 to open until the pressure'in thebraking-cylinder has been diminishedso that the ower of. the magnet issufiicient to return t 1e valve into normal position. It will thus beunderstood that to each strength of current corresponds approximately acertain pressure in the braking-c linder and consequently also a certainbraking-force.

It is now possible by series-or arallel connections or by any series-'para lelconnection of all brake valves of a train to effect thebrakingfof all the cars simultaneously and at one and the same force,whereby an eflec tive control of the train will be obtainedand at thesame time the rolling stock 'is s ared and accidents are prevented. Itwil now be explained how. the said valve can efiect a I reliab e brakingin the case that the-electric current fails. In such case the braking isaccomplished by opening any valve that allows the compressed air to flowout from the.

pipe 22.

The decrease of pressure thus obtained has no influence on the auxiliaryresvoir from the trairvgxplipa is inactive, the pressure in that in theauxilia balanced. In the braking-c ressure,

ervoir, nor on thepressure in the chamber 18. However, the pressure inthe chamber 19 is diminished and the ste'ml is lowered. From theauxiliary reservoir compressedair now will flow through the chamber 18into the braking cylinder, and bykeeping the said valve in the pipe 22open a suilic'ient time the braking action will be stronger andstronger, until the pressure in the braking-cylinder acting in thechamber 17 has become the same as the pressure in the auxiliaryreservoir. Then the valve returns into normal position and remain there,until the pressure inthe pipe 22 is again increased, and the brakes wibe released according as the said pressure increases.

The apparatus shown in Fig. 1 is rovided with a continuous currentmagnet ut may obviously be so modified current magnet may be used.Further slides such as are'used in the pneumatic brake-systems may besubstituted for the valve-construction shown without departing from theprinciple of the invention. Obviously. the present system may so as tosuit the vacuum-brakes. In the device shown in Fig. stem 1 is 3 thevalve- 12 and 13. The diaphragm 12 closes the chamber 17 which is incommunication with the braking-cylinder, while the dia hragm 13 closestwo chambers 18 and'19 o the chamber 19 is in communication with thetrain-pipe 22 and the chamber 18 is connected to an'auxiliary reservoir21. The ,valvethe braking cylinder an the ex austfrom the latter. Atthe. lower end the valve-stem is provided with a valvebody 24 adapted toestablish communication 1 betweenthe train-pipe 22 and the auxiliaryreservoir, "when t e valve-stem is moved downward, so as to; fill theauxiliary reser- The said device works as'-follows:- en thebraking-device reservoirare su stant at the diaphragm 13 is tially thesame. so

linder' 11 is no so'that also the alanced. No current flows through themagnet 15 from the auxiliary resenvoir is cut off 23. 'Th6 brakes'can beap current to the ma 'et-coi valve-stem 1 will e raised and compressedair will flow from the auxiliary reservoir 21 to the brakingcylindertl 1. From the-latter compressed air 17, whereupon. tain brakin-pressure has been reached, be pressed own, so that the supply of air tothe diaphragm, when a cerbe modified likewise combined with an arma true14 or the like, and with two diaphragms the train-pi e and iaphragm ,12.is

c011,; and therefore the valve-stem 1 v is ke tin a middle position by aspring 25 in whic position the air-sup y the slide-valve lied bysupplying f 15, whereby the that an alternating I which stem 1 supportsa-slide-valve 23 controlling the 'su ply of air to now flows into thechamber' will ' reservoir 21.

whereby the pressure in the chamber 19 the braking-cylinder is cut off.If the strength of current in the magnet-coil be increased, the stem 1will again be raised, so that a further quantity of compressed air canflow into the braking-cylinder, until equilibrium is reached. Byincreasin the strength of current to a maximum fulliraking-force will beobtained. For releasing the brakes it is only necessary to decrease thestrength of the electric current, whereby the pressure in the chamber 17on the diaphragm 12 will overcome the attraction of the magnet-coil onthe core or armature 14, so that the valvestem 1 will be lowered andcommunication between the brakin -cylinder 11 and exhaustpipe 26 will beestablished. Simultaneously the valve 24 is opened for admitting afreshquantity of compressed air into the auxiliary The exhaust continuesuntil the brakingpressure has diminished so much that the powers actingon the valvestem 1 again balance each other.

If braking is to be accomplished by'diminishing the pressure in thetrain-pipe, it is only necessary in well known manner to exhaust a partof the air in the train-pipe,

is diminished and the valve-stem 1 will be raised and cause supply ofair to the braking-cylinder, until the powers acting on the valvestemagain balance each other. In analogous manner the brakes may bereleascdby increasing the pressure in the train-pipe.

Instead of havin the magnetic attraction ower counteracted by thepressure in the raking-cylinder for balancing the powers acting onthevalve-stern, one may let the said powers cooperate and be compensatedby a third constant or variable power, whereby a decrease of theelectric attraction power will cause a corresponding increase ordecrease, res ectively,of the braking-pressure, until equi ibrium isreached. Further the usual air-brake-valves may be arranged for beingoperated both electrically and pneuniatically.v For this purpose onemay, as is shown in Fig. 4, provide an electromagnet the armature 14 ofwhich by means of the stem 1 operates the triple-valve of theair-brakesytem when electric current is supplied to the coil 15. Astronger or weaker current through the coil 15 has the same effect as agreater or smaller decrease of the airgpres- The said device may be somodified that the operation of the triple-valve by the electric currentis accomplished indirectly by combining the triplevalve with a piston,diaphragm, or other movable closing-device which normally'has noinfluence on the usual working of the said valve, but is put inoperation for displacing the same into a position for braking by airunder pressure, or vacuum, the strength of which depends on the strengthof current in an electric circuit.

sired changing either the pressure in the tram- Having now described myinvention what i I claim is:

1. An air-brake-apparatus for electric railway-cars, and the like, inwhich the brakes controls the communication between an auxiliaryreservoir and the braking-cylinder and between the latter and theatmosphere, is controlled both by the train-pipe and by the saidelectric circuit in such a manner that the displacing of the saidvalve-body into de-' positions may be accomplished by pipe or thestrength of current in the said controlling circuit or bothsimultaneously.

2. An air brake apparatus for electric cars, and the like, in whic thebrakes are applied or released by means of the variable air pres- I surein a train pipe or by means of an electric controlling circuit,characterized by the fact I that the valve body, which controls thecommunication between an auxiliary reservoir and the braking cylinderand between the latter and the atmos here, is controlled both by thetrain pipe and by the said electric circuit in such a manner that thedisplacing of the said valve body into desired ositions may beaccomplished by changing elther the pressure in the train pipe or thestrength of current in the said controlling circuit or bothsimultaneously, and in which the valve body is operated on the one sideby the electric controlling circuit against the action of the pressurein the braking cylinder, and on the other side by the pressure in thetrain pipe against the action of the pressure in the auxiliary reservoirby means of diaphragms, isionis, or the like, connected to the said vave o y. 1

3. An air brake apparatus for electric railway cars, and the like, inwhich the brakes are applied or released by means of the variable alrpressure in a train pipe or by means of an electric controlling circuit,characterized by the fact that the valve body, which controls thecommunication between anauxiliary reservoir and the braking cylinder andbetween the latter and the atmosphere, is controlled both by the trainpipe and by the said electric circuit in such a manner that thedisplacing'of the said valve body into desired positions may beaccomplished by chang ng either the pressure in the train pipe or thestrength of current in the said controlling circuit or bothsimultaneously, and in which the valve body is o erated on the one sideby the electric control ing circuit against the action of the pressurein the braking cylinder, and on the other side by the pressure in thetrain pipe against the action of the pressure in the auxiliary reservoirby means of diaphragms, plstons, or the like, connected to the saidvalve body, and further characterized by the fact that for 0 crating thevalve body the electric contro ling circuit and the pressure in thebraking cylinder 'work in one and the same direction and are compensatedby a constant or yielding resistance which in equilibrium keeps thevalve body in a middle position in wh ch the braking cylinder is cut offboth from the auxiliary reservoir and from the atmosphere, whiledestruction 'of the equilibrium 1n the one direction or theother'willcause a displacing of the valve body so as to-put the braking cylinderin communication with the auxiliary reservoir or with the atmosphere.

4. An air brake apparatus'for electric railway cars, and the like, inwhich the brakes are applied or released by meansvof the vari- 'able airpressure in a train pipe or by means of an electric controlling circuit,characterized b the fact that the valve body, which contro s thecommunication between an au X iliary reservoir and the braking cylinderand between the latter and the atmosphere, is controlled both by thetrain pipe and by the said electric circuit in such a manner that thedisplacing of the said valve body into desired positions may beaccomplished by changingeither the pressure in the train pipe or thestrength of current in the said controlling circuit 01 bothsimultaneously, and furvalve body in a pneumatic brake apparatus isplaced under the influence of an electromagnet inserted in an electriccontrolling circuit in such a manner that the said valve body bychanging the strength of current in will be I ther characterized by thefact that the triple caused to make the same movement as are caused bychanging the pressure in the train pi e, while the, electric operationdevice w en 1n zero position has no lnfluence on the pneumatic device.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

RAGNAR WIKANDER.

Witnesses: 4

EVALD DELMAR, JOHN DELMAR.

